The present invention relates generally to coil spring assemblies. The coil springs assemblies may be advantageously incorporated into an innerspring mattress.
A variety of mattresses with coil spring assemblies are known. Many of these mattresses are designed to have uniform firmness across the entire mattress. Each spring in the mattress is designed to exert the same resistance force for a given deformation, even though the weight which the spring is supporting typically varies substantially. For example, individuals having different body weights may share a bed. Moreover, the weight of different regions of an individual""s body can vary, such as the head region, torso region and the leg region. These different regions of the body may exert different forces in different regions of the mattress. For example, the head and leg region of the body may exert less force in regions of the mattress compared to the torso region and would thus result in the mattress sagging in the region of the torso.
Methods of making coil spring assemblies having regions of varying firmness have included increasing the number and density of coil springs, as well as using firmer springs, in selected regions of the assembly. Notwithstanding the variety of coil spring assemblies having regions of varying firmness known in the art, there is a continuing need for improved coil spring assemblies, especially coil spring assemblies having regions of varying firmness. The present invention addresses this need.
The present invention relates to coil spring assemblies. The coil spring assemblies may advantageously be incorporated into a mattress. In one aspect of the invention, a coil spring assembly is provided that includes rows of coil springs, a top securing sheet and a bottom securing sheet wherein the assembly is partitioned into at least two sections of varying firmness. The firmer section is formed from coil springs having a height in their relaxed state larger than the height of coil springs in the other section in their relaxed state. Each of the coil springs has a top surface, a bottom surface and a longitudinal axis. Each of the coil springs are further encased in a pocket. The pocket includes a top surface, a bottom surface and a side wall connecting the top surface and bottom surface and may be formed from fabric. Each of the fabric pockets may be, in one embodiment, interconnected with an adjacent fabric pocket within the same row. A plurality of the coil springs are perimetrical coil springs. The rows of coil springs are positioned between the top securing sheet and the bottom securing sheet wherein each sheet has an inner face and an outer face.
In yet another aspect of the invention, the coil spring assemblies described above may further include top and/or bottom border members. In an embodiment of a coil spring assembly including both top and bottom border members, the rows of coil springs are further positioned between the top and bottom border members.
It is an object of the invention to provide improved coil spring assemblies.
It is a further object of the invention to provide coil spring assemblies having varying sections of firmness.
These and other objects and advantages of the present invention will be apparent from the description herein.